Pressure-relief device



Nov. 11, 1930. I c. D. HELM 1,781,227

PRESSURE RELIEF DEVICE Filed Sept. l5 1928 I -5- I 20 zzj INVENTOR CLYDE D- IIELM- ATTORNEY L Patented Nov. 11, 1930 ,j- NI ED. "STATES PATENT OFFICE-:1

cLYDE D. HELlVLOF FORT WORTH, TEXAS I messvmemm nnvrcn I Application filed September 15, 1928. Serial No. 305,254f

'10 will be more'particularly pointed out in the claims.

Reference is had to the accompanying drawings which form a part of this application." Fig. 1 is a side elevation ofthe valve.

-Fig. 2 is a plan view of the same.

Fig. 3 is a vertical section of the casings.

Fig. 4 is a horizontal section, taken on the line 44 of Fig. 5.

Fig. 5 is a side elevation of the valve cylinder or barrel.

Similar characters of reference are used to indicate the same parts throughout the several views.

The valve is provided with a casing 1 which serves as a supporting frame. The casing 1 is cored out in thejinterior to form a pas-.

sage 2 for the passage of oil or other liquid out through the discharge 3. A cylinder 4 is mounted in the casing 1 and guided and held in place by two annular shoulders 5 which are formed as a result of coring out the casing 1. The cylinder 4 is fixedly locked in place by M an annular flange 6 and by a nut 7 which is screwed on the cylinder above the upper shoulder 5. The casing 1 is provided with a cap 8 which is attached to a flange 9 by screw bolts 10. The casing 1 is in communication with the main flow or supply line by means of a connecting pipe 11 and the discharge is adapted to discharge into a waste line or over flow line 12 which will deliver the oil or other liquid forced through the casing 1 to a reservoir so that pumps can force the overflow back into the main supply line (not shown). The cylinder 4 is provided with a plurality of discharge ports 18 which dis-. charge the excess oil or other liquid into the annular passage 2.

A piston or plunger 14 is mounted in the cylinder 4 moves vertically therein.

This piston is provided with a stem or piston rod 15. This piston rod 15 is provided with an annular flange 16 which servesv as a guide for the movement of the piston 14. The rod rod 15 is adapted to move freely through the cap 8, the cap not being air-tight. The piston rod 15 has racks 16 formed on opposite sides thereof. Means are provided for retarding and controlling the upward movement of the piston 14. I Fulcrum bearings 17 are formed on the cap 8 for thelever 18 and fulcrum bearings-19 are formed onthe cap 8 for the lever. 20. A fulcrum 23 for lever 18 is pivotally mounted inthe bearings 17 and a pinion 22 is rigid with the fulcrum 21 and meshes with a rack 16 on the piston rod 15; A fulcrum 21 for lever 20 is pivotally mounted in the bearings 19 and a pinion 24 is rigid with fulcrum 23and meshes with a rack 16. The pinion 22 and its fulcrum21 are rigid with the lever2O and the pinion 24 andits fulcrum 23 are rigid with the lever 18. Weights 25 may be adjustably mounted on the levers 18 and 2O if necessary. The weights can be moved more or less on'the levers 18 and 20 to adapt the levers to afford the required res stance.

The pressure in supply lines sometimes becomes too great by reason of too much oil being forced through the lines and this pressure must be relieved. In the operation of the valve above described, when the pressure is becoming too great, the oil coming through the pipe 11 will force the piston 14 upwardly and past the ports 13; As soon as the ports 13 are opened the liquid will commence to "the piston 14 down. In forcing the piston 14 upwardly, the pressure must be sufficient to raise the outer ends of the levers 18 and 20 with their weights 25 by reason of the rack and pinion connection above described. i As the pressure inthe supply.linedecreasesxthe flow through the ports '13 into the annular piston 14 will be forced downwardly the levers 18 and 20 and their Weights 25. The

relief valve thus works automatically to lines.

WhatI claim, is- J p 1. A-- pressure relief device comprising a maintain the required pressure in the supply casing having intake and'di'scharge' portsga cylinder mountedin said casing, said casing having an annular cavity therem commumeating with said discharge port, means for locking said cylinder in said casing including an interior flange 1n sald casing'andanexterior flange on said cylinder and a nut pressure 7 relief device comprising a casing having intake and discharge ports a H cylinder mounted in said casing, said casing having anannular cavltysurrounding sa1d cylinder'and communicating withisaid discharge port,'means for locking said cylinder in said casingjinclu ding an interiorflange. in said caslng and an exterlo'r flange on said cylinder and a nut screwed on said cylinder and clamping said flanges together, said cylinder having ports communicating with said cavity, a piston-mounted in said'cylinder and adapted by pressure ofpassing liquidto open and close said cylinder ports automatically,

a piston rod for said piston projecting-out of said casing and racks formed on opposite sides of said rod, and levers fulcrumed on said casing andprovidedwith pinionsirigid therewithadapted to engage said racks.

3. A pressure relief device comprisinga casing having intake and discharge ports, a

cap closing one end of said casing, acylinder mounted. in said casing, said casing having a cavity surrounding said cylinder'and communicating with said discharge, said cylinder having a plurality of discharge ports into said cavity, apiston movable in said cylinder and adapted by pressure of passing liquid to open and close the ports therein automatically, forrelieving excessive pressure in a supply line and conserving the I liquid, a pistonrod for said piston movable freely through said cap and provided with ing, said casing having a circular cavity therein about said cylinder and having a V waste discharge connection and said cylinder having discharge portscommunicating. with said cavity, a piston moving vertically inisaid cylinder for opening and closing "said cylinder ports automatically for relieving excessive pressure in .a supplyline and conserving the liquld, racks formed on said piston, bearing members rigid with said casing, pinions provided with fulcrum shafts rigid therewith and journaled in said bearings,

and levers provided with adjustable weights and rigid with said: shafts.

5. A pressure relief device comprising a casing having. intake and exhaust ports, a cylinder mounted in said casing and prolar flange below said cavity, means for locking said cylinderin said casing, including means for clamping said cylinder flanges .vided with an exterior flange, said casing having an annularcavlty therein communicatlng with said discharge port and an annuagainst said casing flange,- said, cylinder hav-- ing ports communicating with said cavity, a piston mounted in said cylinder and adapted to open and close saidcylinder ports automatically for relieving excessive pressure and conserving the liquid, and means for guiding saidpiston; including a piston rod rigid with said piston and an-annular flange on said rod and movable in said cylinder.

6. A pressure relief device comprising a casing having intake and exhaust ports and an 'annular interior cavity therein and an annular interior flange belowsaid' cavity, a cylinder mounted in said casing and'providedwithports communicating withsaid cavity and having an annular exterior flange engaging theinterior flange of said casing,

means for forcing said cylinder flange I against said casing flange, a piston provided with'a rigid stemiand a cylindrical guide flange rigid with said stem mounted in said cylinder, and means for retarding the move ment of said piston during excessive pressure and forquickl restoring the piston-to normal position a ter the pressure is relieved.

In testimony whereof, I set my hand, this 12th day of July, 1928;

a CLYDE n, HELM.

racks on opposite sides thereof, two pairs of vbearing members formed on said cap, fulcrum shafts journaled in 'said bearing members and pinions rigid with said shafts and adapted: to engage said racks, and levers rigid with saidshafts and actuatedthere'by.

' 4; An automatic pressure relief device comprising a casing connected to a supply line,acylinder fixedly mounted, in said cas- 

